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United States Patent | 5,294,576 |
Mizushima ,   et al. | March 15, 1994 |
A mullite ceramic composition comprises mullite powder as a raw material; at least one of a rare earth element compound and an alkaline earth element compound; and at least one of a Group 6B vanadium compound, niobium compound and a tantalum compound, and the mixture is fired.
Inventors: | Mizushima; Kihou (Nagano, JP); Horiuchi; Michio (Koshoku, JP) |
Assignee: | Shinko Electric Industries Co., Ltd. (Nagano, JP) |
Appl. No.: | 990375 |
Filed: | December 15, 1992 |
Jan 13, 1988[JP] | 63-5374 |
Current U.S. Class: | 501/128; 501/5; 501/153; 501/154 |
Intern'l Class: | C04B 035/19 |
Field of Search: | 501/5,128,153,154 |
H302 | Jul., 1987 | Nevitt et al. | 501/127. |
4094690 | Jun., 1978 | Morton | 501/95. |
4201561 | May., 1980 | Pierson et al. | 65/012. |
4336303 | Jun., 1982 | Rittler | 501/18. |
4770673 | Sep., 1988 | Ketcham et al. | 501/103. |
4935390 | Jun., 1990 | Horiuchi et al. | 501/128. |
4963514 | Oct., 1990 | Horiuchi et al. | 501/128. |
Foreign Patent Documents | |||
0237103 | Sep., 1987 | EP. | |
63-239154 | Oct., 1988 | JP. | |
3239154 | Oct., 1988 | JP | . |
63-303856 | Dec., 1988 | JP. |
"Fracture Toughness of Al.sub.2 O.sub.3 with an Unstabilized ZrO.sub.2 Dispensed Phase", Nils Claussen, Journal of American Ceramic Society, vol. 59, No. 1-2, Jan.-Feb. 1976, pp. 49-51. "K.sub.IC Calculations for Some Mullite-Zirconia Composites Prepared by Reaction Sintering", de la Lastra et al., Journal of Materials Science Letters 4 (1985) 1099-1101. "Structural Imperfections", Introduction to Ceramics, Chapter 4, pp. 125-139. "Role of Impurities on Formation of Mullite from Kaolinite and Al.sub.2 O.sub.3 SiO.sub.2 Mixtures", Johnson et al., Ceramic Bulletin, vol. 61, No. 8 (1982) pp. 838-842. "Glass Properties in the Yttria-Alumina-Silica System", Hyatt et al., Communications of the American Ceramic Society, 70(10) Oct. 1987, pp. C-283-C-287. Chemical Principles, Third Edition, Dickerson et al., 1979, pp. 49-51. "Fracture Toughness of Al.sub.2 O.sub.3 with an Unstabilized ZrO.sub.2 Dispersed Phase": Nils Claussen; Journal of the American Ceramic Society; vol. 59, No. 1-2, pp. 49-51. "K.sub.aIC Calculations for Some Mullite-Zirconia Composites Prepared by Reaction Sintering"; Baudin de la Lasztra et al.; Journal of Materials Science Letters 4 (1985): pp. 1099-1101. "Structural Imperfections", (chapter 4); Introduction to Ceramics (1960) Kingery. "Chemical Principles" Third Edition, 1979 pp. 49-51 by Dickerson et al. |
TABLE 1 __________________________________________________________________________ THERMAL DIELECTRIC FLEXURAL EXPANSION FLECK CONSTANT STRENGTH COEFFICIENT GENER- ADDITIVES (1 MHz 20.degree. C.) (kg/mm.sup.2) (.times.10.sup.-6 /.degree.C.) COLOR ATION __________________________________________________________________________ Example 1 Y.sub.2 O.sub.3 (2 wt %) Nb.sub.2 O.sub.5 (1 wt %) 6.5 22.7 4.5 White -- Comparative Y.sub.2 O.sub.3 (2 wt %) 6.4 21.2 4.2 White .smallcircle. Example 1 Example 2 Y.sub.2 O.sub.3 (2 wt %) MoO.sub.3 (1 wt %) Nb.sub.2 O.sub.5 7.0 26.0 4.9 Black -- (1 wt %) Comparative Y.sub.2 O.sub.3 (2 wt %) MoO.sub.3 (1 wt %) 6.9 24.5 4.5 Black .smallcircle. Example 2 Example 3 MgO (2 wt %) Nb.sub.2 O.sub.5 (1 wt %) 6.6 17.6 4.3 White -- Comparative MgO (2 wt %) 6.4 16.1 4.1 White .smallcircle. Example 3 Example 4 Y.sub.2 O.sub.3 (2 wt %) Ta.sub.2 O.sub.5 (1.5 wt 7.0 20.6 4.3 White -- Example 5 Y.sub.2 O.sub.3 (2 wt %) V.sub.2 O.sub.5 (1 wt %) 6.5 21.9 4.5 Black -- __________________________________________________________________________